1. Field of the Invention:
The present invention relates to a highly efficient continuous process for the preparation of bromine whereby chlorine is introduced into an aqueous solution which contains a bromide, so as to generate free bromine.
2. Description of Prior Art:
In the past, bromine has been produced from bromide containing solutions by the "Kubierscky's distillation method", or a modification thereof. In that method a bromide solution is fed counter-currently in a multiple plate contact tower, made of granite or similar effect material. Chlorine gas is fed into the bottom of the tower, and contacts the bromide solution which is fed from the top of the column. Bromine, which is produced by the reaction, is distilled from the top of the tower by the introduction of steam from the bottom of the tower, and is recovered.
One difficulty with the prior art procedures, however, is that both chlorine and steam must be simultaneously introduced into the column. This in turn requires that the temperature of the entire tower be kept high, which is quite disadvantageous for the exothermic vapor-liquid reaction of the chlorine with the bromide containing solution. Moreover, bromine vapor has a significantly higher specific gravity (about 10 times) compared to that of steam, so that bromine gas will not rise readily in the tower, but will tend to accumulate in a lower layer. Invariably, some of bromine is discharged from the bottom of the tower. In order to distill all of bromine from the top of the tower and to overcome the high resistance of the tower, the steam consumption must be further increased.